123664809615 has 16 divisors (see below), whose sum is σ = 202465177728. Its totient is φ = 64420737696.

The previous prime is 123664809581. The next prime is 123664809641. The reversal of 123664809615 is 516908466321.

It is not a de Polignac number, because 123664809615 - 2¹³ = 123664801423 is a prime.

It is a super-2 number, since 2×123664809615² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95863549 + ... + 95864838.

It is an arithmetic number, because the mean of its divisors is an integer number (12654073608).

Almost surely, 2^123664809615 is an apocalyptic number.

123664809615 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

123664809615 is a deficient number, since it is larger than the sum of its proper divisors (78800368113).

123664809615 is a wasteful number, since it uses less digits than its factorization.

123664809615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 191728438.

The product of its (nonzero) digits is 1866240, while the sum is 51.

The spelling of 123664809615 in words is "one hundred twenty-three billion, six hundred sixty-four million, eight hundred nine thousand, six hundred fifteen".